Germany confirmed Hackers targeted federal government’s computer networks in December. The breach involved malicious software and hacked more sensitive data than the German parliament’s breach of 2015, according to a leading member of Chancellor Angela Merkel’s conservatives.

Sources unveiled that the malicious software had been situated up to a year earlier and suspecting a notorious Russian hacking group.

Parliament’s committee for digital affairs conducted an emergency meeting to review the details and demanded more information about the attack which then became public on Wednesday.

Patrick Sensburg, parliamentary committee’s member that supervises German intelligence agencies said that it would take some time for further investigation.

According to sources, a Russian hacking group known as APT28 hacked into Germany’s Foreign and Defense Ministries and targeted sensitive data. The attack was uncovered in December and it could have remained for as long as a year.

The Interior Ministry confirmed a hack of the federal government’s computer networks had been “isolated” and contained.

Sources said, the government’s ‘Informationsverbund Berlin-Bonn’ (IVBB) network, specifically designed communications platform was involved in the cyberattack. The Chancellery, federal ministries, the German parliament, the Federal Audit Office and several security institutions in Berlin and Bonn, exclusively uses the network.

National Security Agency (NSA) and U.S. Cyber Command chief Adm. Michael Rogers says, “Everything, both as the director of the NSA and what I see on the Cyber Command side, leads me to believe that if we don’t change the dynamic here, this is going to continue and 2016 won’t be viewed as something isolated,” “This is something that will be sustained over time.”